Vent-sealing percussion-primer



F. s. L. JOHNSON. VENT SEALING PERCUSSION PRIMER.

APPLICATION FILED MAY 14. i919- n 9 1 0 2 D .W m. m P

if! j www M, 3%, M 5W,

erase FREDERICK onorrnnv LEES JoENsoN, 0F v/EsTMINs'rER, ENGLAND, ASSIGNOR T0 vroKERs minrrnn, or wns rlvirusrnn, ENGLAND.

VENT-SEALING PERCUSSION -PRIMER.

Specification of Letters Patent. Patent d D 2% 1921 Application filed May 14, 1919.

Serial No. 297,151.

(GRANTED UNDER THE PROVISIONS OF THE ACT OF MARCH 3, 1921, 41 STAT. 14,1313.)

. T 0 all whom it may concern:

Be it known that I, FREDERICK Gnorrnny Lnns JoHNsoN, a sub ect oi the King of Great Britain, resldmg at viclrers House,

Broadway, Westminster, in the county of #130,096, and of which the following is a specification.

This invention relates to vent sealing percussion tubes or primers of the ball and conical seating type and has for its chief object to effect the sealing of the tube before any gas pressure from the magazine, which is necessary to actuate the usual ball seal, can be effective.

According to this invention a charge of fulminate or detonating composition through which the magazine is fired is associated with a sealing pellet, preferably of copper, adapted on ignition of the said composition to be driven against the conical seat-mg to form a seal, without depending on the gas pressure due to the ignition of the magazine. In order that the said invention may be 7 clearly understood and readily carried into effect, we will now describe the same more fully with reference to the accompanying drawings, in which:-

Figure 1 is a longitudinal section of a vent sealing tube embodying this invention; and I Fig. 2 is a detail view showing a slight modification.

A is the vent sealing tube body having at one end a magazine a filled with gunpowder. B is the screw plug at the rear end of the powder chamber or magazine, provided with a tubular'nipple C is the conical chamber inside the tube body. D is the copper sealing pellet fitting over the from the flash aassa 'e (5 leadin to the b b powder charge in the chamber a by a thin copper disk or dlaphragm at 21*.

The copper sealing pellet D fits over the end of the nipple b as a cap and the rounded part of thepellet faces the contracting portion of the conical chamber C, through which is ledthe flash from the percussion cap E in the base of the tube A, igniting the fulminate or detonating charge I) through small openings 6 at the baseoi the nipple below thepellet cap. At the apex of the conical chamber flash passages a lead to the percussion cap E.

On firing the percussion cap E-the flash passes from the cap through the' conical chamber 0, igniting the tulminate or detonating charge I) at the nipple b, the action of the explosion of the charge driving oil'- the sealing pellet D and forcing it into the conical seating of the chamber C, so as to close the tube or primer completely. At practically the same moment, the powder charge in the magazine a is ignited by the flash from the detonating composition. The

' charge.

In aslight modification shown in Fig. 2 the pellet D is not fitted closely on the end of the nipple b but is separated from the endby a small auxiliary charge b o'l the detonating composition separated from the initial charge 6 bythe length of the nipple. In this'case the charge 6 is first fired by the flash from the percussion cap and the flash then passes through the central passage of the nipple back to the auxiliary charge 6*. This insures the effective action or" the pellet since it expands the pellet as it drives it ofi' the nipple into the conical recess.

l/Vhat I claim and desire to secure by Let ters Patent of the United States is 1. In a vent sealing percussion primer, a primer body provided with a flash passage and a conical chamber forming a seating, a magazine charge, a member closing the end of the magazine chamber and provided with a passage leading from the conical chamber to the magazine chamber, a small detonating charge placed within the said passage and separated from but communicating with the magazine charge, and a sealing pellet at the rear end of the said passage which pellet is adapted to be driven into the conical seating by the pressure due 2. In a vent sealing percussion primer, a primer body provided with a flash passage and a conical chamber formin a seating, a magazine charge, a plug closmg the end of the magazine chamber, a tubular nipple von the plug, a charge of detonatin composition' carried by the plug and a sea ing pellet FREDERICK GEOFFREY LEES JOHNSON. 

